Unfortunately, what you describe was not uncommon on some early Pietta revolvers. They had quality control problems which have reportedly been corrected on their current products.

The gun should be safe to shoot. The misalignments you describe could, and probably will, result in some lead shaving and leading in the bore but are unlikely to damage the gun or cause injury (I'd suggest you not allow anyone to stand next to you while shooting, however).

Just to be sure, though, in case your estimates of the amount of misalignment is in error, I'd have a gunsmith check it out first.